Difficult question, need pro. Does PPM/EC actually matter? (I elaborate in post).

[NateGrows]

Does EC/PPM actually matter?

Hypothetically, say I have 500PPM. The 500PPM consists of solely base nutrients (NPK/CalMag).

I am getting nute burn from the 500PPM.

If I then add an additional nutrient that the plant is currently not receiving (say, Silica) and the PPM then increases to 600 - will this cause the nutrient burn to progress (get worse)? Or does PPM not matter at all in situation because I'm not adding nutrients that are actually causing the nute burn.

Rephrased: do plants have a total EC/PPM that they can possibly 'digest', or are usable/'digestable' PPM's solely based on the concentration of each particular nutrient?

I cannot find anything regarding this issue on the entirety of any forum on the internet (probably just don't know the correct terminology )...

If someone is able to chime in with solid science (or experience), I'd be greatly appreciative.

All aboard the learning train!

Thank you!

 

[NateGrows]

Picture of my ladies painted nails for some fun in this thread of completely hypothetical situations


Please tell me I can add silica without hurting her

 

[Eledin]

You can add silica without hurting her. PPM control is more for the NPK. I grow in organic and I dont even meassure EC because its not plain nutrients, there's a lot of PPM for the microorganisms to eat and poop for the plant and slow release stuff in general. If youre using sinthetic or biomineral, dont go above the recommended EC but if youre gonna add an additive that doesnt have any NPK you can go above the recommended EC. Just be careful if youre gonna add silica in liquid form, if its potassium silicate you can still overfertilize, if its silicium dioxide youre good and if its diatomaceous earth youre good too as long as you dont abuse it.
IMPORTANT: There's people much more experienced than me in this forum so lets see what they think.

 

[Eledin]

I forgot a couple of important questions, youre growin on peat right? Because if its coco then you need to be even more careful with the EC. As long as youre not giving her a lot of fast absorption stuff or saturating the soil you should be fine. I add silica in liquid form and in powder form (diatomaceous earth). Going above the EC because youre using an additive that doesnt have any NPK shouldnt hurt them, that said you cant just start adding a lot of stuff, but just the silica should be completely fine if youre using peat. What nutes are you using?

 

[Eledin]

Picture of my ladies painted nails for some fun in this thread of completely hypothetical situations


Please tell me I can add silica without hurting her

View attachment 2093056

She looks healthy overall, those yellow tips I assume is because of the NPK? Or light stress? You said you overfertilized them a bit but looking at the state of the plant is nothing serious, just go to the previous dose. I always burn some tips when searching for the maxium dose that the plant will allow me togive her.

 

[NateGrows]

She looks healthy overall, those yellow tips I assume is because of the NPK? Or light stress? You said you overfertilized them a bit but looking at the state of the plant is nothing serious, just go to the previous dose. I always burn some tips when searching for the maxium dose that the plant will allow me togive her.

Hey Eledin. Yeah, nute burn is due to NPK. I'm running autopots so the dose is incredibly low compared to manually feeding, but I'm very happy with the results.

Just wanted to add silica back into my feeding schedule as the difference it made was incredible (and I've since heard that trichomes are made of silica), so I really didn't want to deprive her of it anymore - so thanks for reassuring me it's okay..

Also, thank you for taking the time to educate me mate, I truly appreciate it. Hoping more people chime in but I'm very satisfied with your response.

Every time I think I have a decent understanding of this plant, I'm humbled and reminded I don't know shit lol. Talk about Dunning-Kruger.

Again, thanks for taking the time.

Take care, happy new year & may your grows be absolutely fire

 

[Eledin]

My pleassure, and dont forget the calcium! Trichomes are made of it aswell. In fact everything in the plant needs calcium to be built, just be careful with the calmag because they usually come with nitrogen. Adding dolomite to the soil next time will help too, now its too late cause its not water soluble. If you wanna make fast absorption calcium just save some eggshells, buy apple cider vinegar, crush the egshells into powder or small chunks and use a ratio of 1 egg shells 2 vinegar. Stir well and let it settle (Use a decently big container, its gonna foam a lot), once its settled take a sample and meassure the PH, if its in between 6,5 and 7 youre good to go, if not add more eggshell powder. The acetic acid from the vinegar is neutralized when it interacts with the calcium carbonate, liberating the carbon (hence the foam) and leaving just the calcium behind. Once you have the PH you want, strain it through a coffee filter or a cloth filter to remove chunks of egg (Dont pour all the eggshells sitting on the bottom or youre gonna stay forever til it drains) and then add 10ml per liter of water once per week. You can use it foliar or add to the reservoir. Apple cider vinegar is less acidic than white vinegar, so you dont need as much eggshell to counter the acidity, and contains more nutrients for the plant in small doses.
Happy new year! Hope your grows are fire too!

 

[Eledin]

Forgot to mention, I bet you know already but just in case I dont wanna ruin your grow. Never use foliar in flower, only in veg. Also, besides the dolomite mixed with the soil for calcium you can also add food grade diatomaceous earth for silica. DE is 80-90% silica. There's calcinated DE too but dolomite lime also adds magnessium which is vital for the calcium to be absorved properly so I go with non calcinated DE and dolomite. This is only if youre using peat, if youre using coco you can still add it but in less quantities because the coco wont hold much of it. I combine ammended soil with top dressings and liquids.
EDIT: In case you wanna use the fast absorption calcium from the eggshells it would be nice to use some epsom salts aswell, theyre water soluble and will give you the magnessium you need for the calcium and also some sulphur. Then you will have a homemade fast absorption calmag without nitrogen and with sulphur.

 

[NateGrows]

Forgot to mention, I bet you know already but just in case I dont wanna ruin your grow. Never use foliar in flower, only in veg. Also, besides the dolomite mixed with the soil for calcium you can also add food grade diatomaceous earth for silica. DE is 80-90% silica. There's calcinated DE too but dolomite lime also adds magnessium which is vital for the calcium to be absorved properly so I go with non calcinated DE and dolomite. This is only if youre using peat, if youre using coco you can still add it but in less quantities because the coco wont hold much of it. I combine ammended soil with top dressings and liquids.
EDIT: In case you wanna use the fast absorption calcium from the eggshells it would be nice to use some epsom salts aswell, theyre water soluble and will give you the magnessium you need for the calcium and also some sulphur. Then you will have a homemade fast absorption calmag without nitrogen and with sulphur.

Thanks for the knowledge bomb mate, you're a legend.

 

[ArtfulCodger]

Osmotic pressure causes water to flow into or out of the plant. The direction is determined by the concentration of the fluids inside the roots (typically/mostly sugars) and outside the roots (e.g. nutrient ions). If the concentration is higher inside the roots, water moves into the plant. If the concentration is higher outside the roots, water moves out of the plant. What we call nute burn is really the leaf tips (and edges, if it goes long enough) getting dehydrated as water flows out of the plant. My understanding is that the distinction between base nutes (NPK) and other elements is irrelevant. We could create a "nute burn" situation (reversing the osmotic pressure) using a variety of soluble substances. If I've got this wrong, I'm happy to be corrected. I'm a hobbyist, not a scientist.

 

[NateGrows]

Osmotic pressure causes water to flow into or out of the plant. The direction is determined by the concentration of the fluids inside the roots (typically/mostly sugars) and outside the roots (e.g. nutrient ions). If the concentration is higher inside the roots, water moves into the plant. If the concentration is higher outside the roots, water moves out of the plant. What we call nute burn is really the leaf tips (and edges, if it goes long enough) getting dehydrated as water flows out of the plant. My understanding is that the distinction between base nutes (NPK) and other elements is irrelevant. We could create a "nute burn" situation (reversing the osmotic pressure) using a variety of soluble substances. If I've got this wrong, I'm happy to be corrected. I'm a hobbyist, not a scientist.

Incredible run down. For a hobbyist, you sure sound like you should be running a large facility lol.

Thank you for taking the time Codger. Legend.

 

[Eledin]

Osmotic pressure causes water to flow into or out of the plant. The direction is determined by the concentration of the fluids inside the roots (typically/mostly sugars) and outside the roots (e.g. nutrient ions). If the concentration is higher inside the roots, water moves into the plant. If the concentration is higher outside the roots, water moves out of the plant. What we call nute burn is really the leaf tips (and edges, if it goes long enough) getting dehydrated as water flows out of the plant. My understanding is that the distinction between base nutes (NPK) and other elements is irrelevant. We could create a "nute burn" situation (reversing the osmotic pressure) using a variety of soluble substances. If I've got this wrong, I'm happy to be corrected. I'm a hobbyist, not a scientist.

Thanks for chiming in, I was afraid I was gonna be the only one to respond to the post and I always doubt myself but I thought it was better than nothing. There's one thing that I dont understand if what you say is correct and maybe it has a simple explanation that I just cant think of, but why that doesnt apply to organic as much as it does with synthetics? When you grow organic you can expect higher PPM right? And its not a problem, because most of that stuff is either gonna release slowly or its what the plant needs in that time. If the plant releases water based on max ammount of PPM no matter what you put in, why can you have higher PPM in organic with no negative consecuences?
EDIT: Also what would be the solution if he wants to add calcium, magnessium and silica? Mantain the PPM at less than 500 by reducing the NPK once a month for example? Or he shouldnt do it at all? I think adding calcium and silica benefits the plant a lot but Im not sure how he can do it safely after reading you.

 

[LoveGrowingIt]

What about transpiration? Isn't that the basic mechanism for the flow of water and nutrients?